Bill vs EOB

I Got an EOB After My Insurance Claim Was Denied

An EOB after a claim denial explains the denial reason and any patient responsibility. You may still owe the full amount.

Updated August 16, 2026 · 6 min read

Quick answer

An EOB after a claim denial explains why your plan denied the claim and what you owe. If the claim was denied, you may be responsible for the full billed amount. You have the right to appeal.

Understanding a Denial EOB

A denial EOB looks similar to a paid EOB but shows $0 insurance paid and the full billed amount as patient responsibility. It will include a denial reason code.

Common Denial Reasons

Claims are denied for many reasons.

  • Not medically necessary - the insurer determined the service was not needed.
  • Prior authorization not obtained - the service required pre-approval.
  • Out-of-network - the provider is not in your plan network.
  • Service not covered - the service is excluded from your plan.
  • Duplicate claim - the service was already processed.

Your Right to Appeal

You have the right to appeal any denied claim. The denial EOB will include instructions. You typically have 60 to 180 days to file, depending on your plan.

Frequently asked questions

Do I have to pay if my claim is denied?

You may owe the full amount if the denial stands. However, you have the right to appeal. Do not pay until you have exhausted your appeal options.

How do I appeal a denied claim?

The denial EOB will include appeal instructions. Typically, you submit a written appeal with supporting documentation within the timeframe listed.

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